Venting closure



D. DONA LDSON VENTING CLOSURE Oct. 22, 1968 Filed Jan. 15, 1968 w v EwrOIz 0A V/O OOA/ALDSO/V ATTORNEYS United States Patent ABSTRACT OF THEDISCLOSURE A vending closure plug for a container opening comprising ahollow body including a pair of members each having an end wall with avent opening and skirt; and a pressure sensitive, elastomeric, apertureddiaphragm element positioned within the body.

The invention relates to venting closures and more particularly to aplug type closure adapted to be threadably received within an opeing ofa wall of a container such as a plastic drum.

It is an object of the invention to provide, in a closure of the typedescribed, an arrangement which will pemit air or other gaseous vaporsto escape from a container to relieve the pressure therein but which atthe same time will prevent the accidental escape of liquids from thecontainer in the event the container is jostled or tipped over from itsnormal standing position.

A more specific object of the invention is the provision, in theinvention of the type described, of a venting closure which includes acylindrical outer body within which is positioned a pressure sensitive,slitted diaphragm insert and a retainer member adapted to hold theinsert in position within the body.

These and other objects of the invention will be apparent from. anexamination of the following description and drawings, wherein:

FIGURE 1 is a perspective view of a venting closure plug embodyingfeatures of the invention;

FIGURE 2 is a transverse vertical section of the structure illustratedin FIGURE 1;

.- FIGURE 3 is a horizontal section taken on line 3-3 of FIGURE 2; and

FIGURE 4 is an exploded perspective view of the elements of the ventingclosure plug shown in FIGURE 1. It will be understood that, for purposesof clarity, certain elements have been intentionally omitted fromcertain views where they are believed to be illustrated to betteradvantage in other views.

Referring now to the drawing for a better understanding of theinvention, and particularly to- FIGURE 1, it will be seen that the novelclosure embodying features of the invention is' shown as beingthreadably received within an aperture 0 in a wall W of a container suchas a plastic drum or barrel.

As best seen in FIGURE 2 the closure includes a generally cylindricalhollow body, indicated generally at 10, which includes a pair of outerand inner cup shaped members 12 and 14, respectively, disposed intelescoping relation to provide an internal cavity 16 within which ispositioned a diaphragm element 18.

Outer body member 12 includes an end wall, indicated generally at 20,having an integral, preferably cylindrical skirt or side Wall 22extending therefrom. Skirt 22 is preferably provided with externalthreads 24 adapted to engage mating threads in the opening of thecontainer wall.

End wall 20 includes a peripheral flange 26 adapted to seat against theouter surface of the container wall when the closure plug is inposition. End wall 20 also includes a central portion in the form of anupwardly projecting ice hollow boss 28 which is preferably formed with acontour of a square or hexagon so that it can be engaged by aconventional wrench to facilitate insertion or removal of the closureplug.

End wall 20 of the outer member is provided with one or more ventopenings 30 which extend through the body of the closure plug andcommunicate with the interior cavity 16.

Still referring to FIGURE 2, it will be seen that in its preferred formthe central portion 32 of boss 28 is connected to the remaining portionof the boss by a relatively thin connecting section 34. The purpose ofthis arrangement is described later in the specification.

Again referring to FIGURE 2, it will be seen that at the free end ofskirt 22 there is integrally formed an inwardly extending peripheralretaining lip or flange 36 the purpose of which is also described laterin the specification.

Diaphragm element 18, as best seen in FIGURES 2 and 4- is also generallycup-shaped and includes a cylindrical side wall 42 having at one endaround end wall 40 and having at the other end a radially outwardlyextending peripheral rim 44 undercut as at 46 to facilitate itsconnection to the inner body member as hereinafter described. End wall40 of the insert is provided with a transverse slit 48 extendingtherethrough, the purpose of which will be described in connection withthe operation of the invention.

As best seen in FIGURE 2 diaphragm element 18 is positioned withincavity 16 of the body with its skirt rim 44 disposed in abuttingposition against the inside surface of outer member end wall 20, and ismaintained in this position within body cavity 16 by a means of innerbody member 14.

As best seen in FIGURE 2 and 4 inner member includes a preferably roundend wall '50 having a generally cylindrical, although preferablytapered, side wall 52 projecting therefrom. The free end edge of sidewall 52 is preferably provided with a chamfer as at 54 adapted to matewith undercut 46 of the element rim 44 to provide snug engagementtherebetween. Inner member 14 may be held in telescoping relation withouter member 12 by means of the inner retaining flange 36 on the freeend edge of the outer member skirt. The purpose of the tapered side wallof the inner member is to permit its skirt to be forced into the outermember skirt the retaining shoulder. Once it is in position theretaining shoulder will engage the end wall of the inner member to keepit in position within the outer member.

End wall 50 of the inner member has a vent opening 56 over which isdisposed an integral bafile plate 58, the purpose of which ishereinafter described. It will be seen that with the baffle 58 locatedover the opening 56 in a bridge-like manner a pair of side vent openings59 are provided at opposite ends of the baffie.

It will be understood that the body members of the plug are preferablyformed from a low density polyethylene, or other material, as dictatedby the chemistry and economics of particular applications, and thepressure sensitive apertured diaphragm element is formed of a moreflexible elastomeric material such as rubber or the like. As shown inthe drawing the diaphragm element end wall is relatively thin comparedwith the side Wall and has formed therein the slit 48. The length of theslit in combination with the dimension of the wall and its thickness maybe coordinated to give the necessary characteristics for whateverpressure and materials may be involved in any particular application.

In operation as fluid pressure in the container reaches a predeterminedamount pressure applied to the diaphragm element end wall causes the endwall to bulge away from the direction of the pressure which in turncauses a parting of the sides adjacent the slit. The thicker side wallof the element eliminates the effects of strain due to assembly in theclamping and sealingflange being transmitted to the element end wall,and it also enables the device to vent into the container at aconsiderable smaller pressure dilierential than is required for ventingoutwards. This is accomplished because the design assures that pressureis applied to the side wall of the insert when venting is required,causing a compression of the slit on outward venting and a widening ofthe slit on inward venting. The magnitude of the pressure that causesthe respective venting can be accommodated over a wide range byappropriate dimensions, starting at almost zero for very thin softunits.

'By the arrangement of the baflie construction of the end wall of theretainer member it will be understood that the side openings 59 are sopositioned that liquid impinging upon the baflie from inside thecontainer will principally splash outward and away from the pressureelement or diaphragm insert so as to minimize the danger of leakage dueto inadvertent surges of liquid against the inner extremity of theclosure member.

Thus it will be seen that the invention provides a closure arrangementof relatively simple design and construction which will afford themaximum protection against dangerous build-up of air pressure within thecontainer and at the same time will minimize the danger of liquid fromthe container through the venting closure in the event the container isaccidentally tipped over or knocked down.

I claim:

1. A venting closure plug for a container, comprising:

(a) a body including:

(i) a pair of hollow, cup-shaped outer and inner members each having anend wall with a vent opening extending therethrough and an integral,generally cylindrical skirt extending therefrom;

(ii) at least a portion of the skirt of the inner member beingtelescopically received within the skirt of the outer member to define acavity between the end walls of respective members;

(b) a pressure sensitive, apertured diaphragm element positioned withinsaid cavity for permitting the flow of fluid between the vent openingsof respective body members to vent the interior of the container whenthe fluid pressure therein exceeds a predetermined amount required toflex said element.

2. A venting closure plug according to claim 1, wherein said outer bodymember end wall includes a boss contoured for engagement with a wrenchand wherein the vent opening is in a side of said boss.

3. A venting closure plug according to claim 1, wherein said outer bodymember end wall has a portion joined to the remainder of the end wall bya relatively thin connecting section which is adapted to rupture andthereby permit the blow-off of said portion, if the pressure in thecontainer exceeds a predetermined amount, to prevent the rupture of theentire container.

4. A venting closure plug according to claim 1, wherein the skirt ofsaid outer body member is threaded for engagement with a threadedopening in the container.

5. A venting closure plug according to claim 1, wherein said membersinclude cooperating means operable to retain the members in telescopingrelation with each other.

6. A venting closure plug according to claim 5, wherein said cooperatingmeans includes a radially inwardly projecting shoulder on the free endof the outer member skirt engageable with the outer surface of the innermember end wall.

7. A venting closure plug according to claim 1,"wherein the inner memberskirt is tapered to facilitate its insertion into the skirt of the outermember.

8. A venting closure plug according to claim 1, wherein said inner andouter members are formed of a thermoplastic material, and the diaphragmelement is formed of an elastomeric material.

9. A venting closure plug according to claim 1, wherein said diaphragmelement is generally cup-shaped and includes:

.(i) a cylindrical side wall;

(ii) a round end wall which is relatively thinner than said side walland which has a transverse slit extending therethrough which is openableupon the application of a predetermined amount of pressure thereagainst.

10. A venting closure plug according to claim 9, and including anannular, radially outwardly projecting, peripheral rim at the free endof said diaphragm element side wall having an axially outer surfaceengageable with the inner surface of said outer member end wall andhaving an axially inner surface engageable with the free end edge ofsaid inner member skirt.

11. A venting closure plug according to claim 10, wherein said diaphragmelement rim inner surface is inclined and wherein the free end edge ofthe inner member skirt is chamfered to provide a tongue and grooveconnection between the inner member and diaphragm insert.

12. A venting closure plug according to claim 1, wherein the innermember end wall includes an integral bridgelike bafiie sectionpositioned over said vent opening to prevent a direct surge of fluidpressure against said diaphragm element.

13. A venting closure plug for an opening in a container, comprising:

(a) a body having a pair of outer and inner cup-shaped members disposedin telescoped relation and each having a vent opening communicating withthe interior of the body;

(b) an elastomeric, apertured diaphragm element positioned within saidbody for permitting the flow of fluid between the vent openings ofrespective body members to vent the interior of the container when thefluid pressure therein exceeds a predetermined amount required to flexsaid insert.

14. A venting closure plug for an opening in a container, comprising:

(a) a hollow body having vent openings at opposite ends;

(b) an elastomeric, apertured diaphragm element positioned within saidbody for permitting the flow of fluid between the vent openings of thebody to vent the interior of the container when the fluid pressuretherein exceeds a predetermined amount required to flex said insert;

(c) said body including means for preventing the surge of fluid from thecontainer directly against said diaphragm insert.

References Cited UNITED STATES PATENTS 2,937,223 5/1960 Thompson 215-563,023,924 3/1962 Boyer 220-44 THERON E. CONDON, Primary Examiner.

GEORGE T. HALL, Assistant Examiner.

